The subject matter of the present invention relates generally to container tank caps having a remotely actuated lock, and in particular to such caps having latch means operated by gas pressure such as pressurized air. The present invention is suitable for use as a fuel tank filler cap such as those used on trucks and other motor vehicles.
Previously, fuel tank caps for automobiles and trucks have been provided with key operated latch means for locking the cap on the fuel tank filler opening to prevent theft of fuel. However, this has the disadvantage that the key may become lost and also requires that the key be transferred from the driver to the service station attendant for unlocking the cap before fuel can be transmitted into the fuel tank. This is extremely inconvenient and if the key is lost the fuel cap cannot be removed. In order to avoid this inconvenience and to provide greater security for locking the tank cap, an air actuated latch means is employed in the tank cap of the present invention. The latch is remotely operated by the driver, for example, while located in his cab merely by opening a suitable air valve such as an electrical switch actuated solenoid valve. The latch may be operated by pressurized air from the same source of air pressure supplying the air brakes or air clutch of the truck or other motor vehicle. Thus, there is very little increased cost for extra equipment when employing the tank cap of the present invention.
The air actuated latch of the present invention is reliable and trouble-free in operation because, among other things, there are no external parts to become dirty. In addition, the tank cap and air latch are resistant to damage by vandalism because all parts are contained within the cap and the fuel tank filler tube. Furthermore, the tank cap cannot be lost because it is permanently attached to an air hose fitting fixed to the vehicle body.